Playing centre-half, Marcel picked up the injury in an aerial clash towards the end of the first half in the 2-0 defeat at Stevenage Borough and was unable to continue after half-time.
The doctor suspected straight away that Marcel had fractured his cheekbone and that's the case
He was unlucky because the Arsenal player has caught him with the top of his head.
"It looks like he'll be out for three to four weeks and it's a shame for Marcel because he's been playing regularly for the reserves and he's done well of late."
Young defender Marcel McKie faces a few weeks out after fracturing his cheekbone on reserve duty against Arsenal.